U.S. Pat. No. 4,402,386 describes an elevator assembly which is powered by a linear motor mounted on the counterweight of the elevator. The armature of the motor is a pole fixed in the elevator hoistway. The sheaves which carry the ropes connecting the counterweight and elevator cab are not traction sheaves, but are merely guide sheaves. Thus, the sheaves in the aforesaid elevator system are not connected to a drive motor, and there is no need to have a machine room, either overhead, or below the cab.
In some areas of the world, safety codes require that overhead sheaves not be installed in the hoistway directly above the roof of the cab. Compliance with these codes results in a very complex roping arrangement, typically requiring two sheaves mounted on the cab frame below the floor of the cab, and wherein a 2/1 roping ratio is used. This arrangement is complicated and costly as it requires extra sheaves and an excess of rope.